The NCP1800 is a constant-current/constant-voltage (CCCV) single-cell charge controller for use with either Li or lithium-polymer batteries. A conditioning and pre-charge phase helps protect and prolong the life of a nearly depleted Li battery by lightly charging it before the onset of full charge. Battery capacity and system safety are also maximized through the NCP1800's better than 1 percent voltage regulation. Integrated voltage and programmable current features offer design versatility by providing various charging options for different Li battery chemistries and capacities. The NCP1800 accommodates either a PNP or PMOS transistor to control battery charging. In the case of the PNP transistor, the device reduces the overall printed-circuit board area needed to implement a charging solution by eliminating the blocking diode.